# TallStackUI: Back to Top
> TallStackUI is a TALL Stack (Tailwind CSS, Alpine.js, Laravel, Livewire)
> component library providing 65+ Blade components for building modern web interfaces.
A floating button that appears when the user scrolls down, allowing them to smoothly scroll back to the top of the page or to a specific anchor element.
## Basic Usage
```blade
```
```blade
```
```blade
```
## Attributes
| Attribute | Type | Default | Description |
|-----------|--------------|----------------|----------------------------------------------------------------------------|
| icon | string\|null | 'chevron-up' | Heroicon name displayed inside the button |
| color | string\|null | 'primary' | Color theme (e.g., primary, red, green, blue) |
| position | string\|null | 'bottom-right' | Screen position: 'bottom-right' or 'bottom-left' |
| anchor | string\|null | null | CSS selector of the element to scroll to instead of the page top |
| immediate | bool | false | Uses instant scroll instead of smooth animation when scrolling back to top |
| square | bool | false | Uses rounded-lg corners instead of fully rounded |
| xs | bool | null | Extra-small size |
| sm | bool | null | Small size |
| md | bool | null | Medium size (default) |
| lg | bool | null | Large size |
## Validation Constraints
- The `position` attribute must be one of: `bottom-left`, `bottom-right`.
## Soft Customization
Soft customization allows you to override default Tailwind CSS classes used by this component at runtime, either through a service provider or scoped per-instance.
### Customization
```php
TallStackUi::customize()
->backToTop()
->block('button.base', 'your-tailwind-classes');
```
### Available Blocks
| Block Name | Purpose |
|-----------------------|-------------------------------------------------------|
| button.base | Base button styles (flex, shadow, focus ring, cursor) |
| button.sizes.xs | Extra-small button dimensions |
| button.sizes.sm | Small button dimensions |
| button.sizes.md | Medium button dimensions |
| button.sizes.lg | Large button dimensions |
| icon.sizes.xs | Extra-small icon dimensions |
| icon.sizes.sm | Small icon dimensions |
| icon.sizes.md | Medium icon dimensions |
| icon.sizes.lg | Large icon dimensions |
| position.bottom-left | Fixed positioning for bottom-left placement |
| position.bottom-right | Fixed positioning for bottom-right placement |